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1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Timers abstract layer
4 * Copyright (c) by Jaroslav Kysela <[email protected]>
5 */
6
7#include <linux/delay.h>
8#include <linux/init.h>
9#include <linux/slab.h>
10#include <linux/time.h>
11#include <linux/mutex.h>
12#include <linux/device.h>
13#include <linux/module.h>
14#include <linux/string.h>
15#include <linux/sched/signal.h>
16#include <linux/anon_inodes.h>
17#include <linux/idr.h>
18#include <sound/core.h>
19#include <sound/timer.h>
20#include <sound/control.h>
21#include <sound/info.h>
22#include <sound/minors.h>
23#include <sound/initval.h>
24#include <linux/kmod.h>
25
26/* internal flags */
27#define SNDRV_TIMER_IFLG_PAUSED 0x00010000
28#define SNDRV_TIMER_IFLG_DEAD 0x00020000
29
30#if IS_ENABLED(CONFIG_SND_HRTIMER)
31#define DEFAULT_TIMER_LIMIT 4
32#else
33#define DEFAULT_TIMER_LIMIT 1
34#endif
35
36static int timer_limit = DEFAULT_TIMER_LIMIT;
37static int timer_tstamp_monotonic = 1;
38MODULE_AUTHOR("Jaroslav Kysela <[email protected]>, Takashi Iwai <[email protected]>");
39MODULE_DESCRIPTION("ALSA timer interface");
40MODULE_LICENSE("GPL");
41module_param(timer_limit, int, 0444);
42MODULE_PARM_DESC(timer_limit, "Maximum global timers in system.");
43module_param(timer_tstamp_monotonic, int, 0444);
44MODULE_PARM_DESC(timer_tstamp_monotonic, "Use posix monotonic clock source for timestamps (default).");
45
46MODULE_ALIAS_CHARDEV(CONFIG_SND_MAJOR, SNDRV_MINOR_TIMER);
47MODULE_ALIAS("devname:snd/timer");
48
49enum timer_tread_format {
50 TREAD_FORMAT_NONE = 0,
51 TREAD_FORMAT_TIME64,
52 TREAD_FORMAT_TIME32,
53};
54
55struct snd_timer_tread32 {
56 int event;
57 s32 tstamp_sec;
58 s32 tstamp_nsec;
59 unsigned int val;
60};
61
62struct snd_timer_tread64 {
63 int event;
64 u8 pad1[4];
65 s64 tstamp_sec;
66 s64 tstamp_nsec;
67 unsigned int val;
68 u8 pad2[4];
69};
70
71struct snd_timer_user {
72 struct snd_timer_instance *timeri;
73 int tread; /* enhanced read with timestamps and events */
74 unsigned long ticks;
75 unsigned long overrun;
76 int qhead;
77 int qtail;
78 int qused;
79 int queue_size;
80 bool disconnected;
81 struct snd_timer_read *queue;
82 struct snd_timer_tread64 *tqueue;
83 spinlock_t qlock;
84 unsigned long last_resolution;
85 unsigned int filter;
86 struct timespec64 tstamp; /* trigger tstamp */
87 wait_queue_head_t qchange_sleep;
88 struct snd_fasync *fasync;
89 struct mutex ioctl_lock;
90};
91
92struct snd_timer_status32 {
93 s32 tstamp_sec; /* Timestamp - last update */
94 s32 tstamp_nsec;
95 unsigned int resolution; /* current period resolution in ns */
96 unsigned int lost; /* counter of master tick lost */
97 unsigned int overrun; /* count of read queue overruns */
98 unsigned int queue; /* used queue size */
99 unsigned char reserved[64]; /* reserved */
100};
101
102#define SNDRV_TIMER_IOCTL_STATUS32 _IOR('T', 0x14, struct snd_timer_status32)
103
104struct snd_timer_status64 {
105 s64 tstamp_sec; /* Timestamp - last update */
106 s64 tstamp_nsec;
107 unsigned int resolution; /* current period resolution in ns */
108 unsigned int lost; /* counter of master tick lost */
109 unsigned int overrun; /* count of read queue overruns */
110 unsigned int queue; /* used queue size */
111 unsigned char reserved[64]; /* reserved */
112};
113
114#ifdef CONFIG_SND_UTIMER
115#define SNDRV_UTIMERS_MAX_COUNT 128
116/* Internal data structure for keeping the state of the userspace-driven timer */
117struct snd_utimer {
118 char *name;
119 struct snd_timer *timer;
120 unsigned int id;
121};
122#endif
123
124#define SNDRV_TIMER_IOCTL_STATUS64 _IOR('T', 0x14, struct snd_timer_status64)
125
126/* list of timers */
127static LIST_HEAD(snd_timer_list);
128
129/* list of slave instances */
130static LIST_HEAD(snd_timer_slave_list);
131
132/* list of open master instances that can accept slave links */
133static LIST_HEAD(snd_timer_master_list);
134
135/* rwlock for timer instance (for trigger actions) */
136static DEFINE_RWLOCK(timeri_lock);
137
138#define MAX_SLAVE_INSTANCES 1000
139static int num_slaves;
140
141static DEFINE_MUTEX(register_mutex);
142
143static int snd_timer_free(struct snd_timer *timer);
144static int snd_timer_dev_free(struct snd_device *device);
145static int snd_timer_dev_register(struct snd_device *device);
146static int snd_timer_dev_disconnect(struct snd_device *device);
147
148static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left);
149
150/*
151 * create a timer instance with the given owner string.
152 */
153struct snd_timer_instance *snd_timer_instance_new(const char *owner)
154{
155 struct snd_timer_instance *timeri;
156
157 timeri = kzalloc_obj(*timeri);
158 if (timeri == NULL)
159 return NULL;
160 timeri->owner = kstrdup(owner, GFP_KERNEL);
161 if (! timeri->owner) {
162 kfree(timeri);
163 return NULL;
164 }
165 INIT_LIST_HEAD(&timeri->open_list);
166 INIT_LIST_HEAD(&timeri->active_list);
167 INIT_LIST_HEAD(&timeri->master_list);
168 INIT_LIST_HEAD(&timeri->ack_list);
169 INIT_LIST_HEAD(&timeri->slave_list_head);
170 INIT_LIST_HEAD(&timeri->slave_active_head);
171
172 return timeri;
173}
174EXPORT_SYMBOL(snd_timer_instance_new);
175
176void snd_timer_instance_free(struct snd_timer_instance *timeri)
177{
178 if (timeri) {
179 if (timeri->private_free)
180 timeri->private_free(timeri);
181 kfree(timeri->owner);
182 kfree(timeri);
183 }
184}
185EXPORT_SYMBOL(snd_timer_instance_free);
186
187/*
188 * find a timer instance from the given timer id
189 */
190static struct snd_timer *snd_timer_find(struct snd_timer_id *tid)
191{
192 struct snd_timer *timer;
193
194 list_for_each_entry(timer, &snd_timer_list, device_list) {
195 if (timer->tmr_class != tid->dev_class)
196 continue;
197 if ((timer->tmr_class == SNDRV_TIMER_CLASS_CARD ||
198 timer->tmr_class == SNDRV_TIMER_CLASS_PCM) &&
199 (timer->card == NULL ||
200 timer->card->number != tid->card))
201 continue;
202 if (timer->tmr_device != tid->device)
203 continue;
204 if (timer->tmr_subdevice != tid->subdevice)
205 continue;
206 return timer;
207 }
208 return NULL;
209}
210
211#ifdef CONFIG_MODULES
212
213static void snd_timer_request(struct snd_timer_id *tid)
214{
215 switch (tid->dev_class) {
216 case SNDRV_TIMER_CLASS_GLOBAL:
217 if (tid->device < timer_limit)
218 request_module("snd-timer-%i", tid->device);
219 break;
220 case SNDRV_TIMER_CLASS_CARD:
221 case SNDRV_TIMER_CLASS_PCM:
222 if (tid->card < snd_ecards_limit)
223 request_module("snd-card-%i", tid->card);
224 break;
225 default:
226 break;
227 }
228}
229
230#endif
231
232/*
233 * refcount management of timer object
234 */
235static void snd_timer_kref_release(struct kref *kref);
236
237static inline void snd_timer_ref_get(struct snd_timer *timer)
238{
239 kref_get(&timer->kref);
240}
241
242static inline void snd_timer_ref_put(struct snd_timer *timer)
243{
244 kref_put(&timer->kref, snd_timer_kref_release);
245}
246
247/*
248 * Return the assigned timer for the instance, NULL if not present;
249 * the caller is responsible to call snd_timeri_timer_put(), or use auto-cleanup
250 */
251struct snd_timer *snd_timeri_timer_get(struct snd_timer_instance *timeri)
252{
253 struct snd_timer *t;
254
255 guard(read_lock_irqsave)(&timeri_lock);
256 t = timeri->timer;
257 if (!t)
258 return NULL;
259 snd_timer_ref_get(t);
260 return t;
261}
262EXPORT_SYMBOL_GPL(snd_timeri_timer_get);
263
264void snd_timeri_timer_put(struct snd_timer *timer)
265{
266 snd_timer_ref_put(timer);
267}
268EXPORT_SYMBOL_GPL(snd_timeri_timer_put);
269
270/* move the slave if it belongs to the master; return 1 if match */
271static int check_matching_master_slave(struct snd_timer_instance *master,
272 struct snd_timer_instance *slave)
273{
274 if (slave->slave_class != master->slave_class ||
275 slave->slave_id != master->slave_id)
276 return 0;
277 if (master->timer->num_instances >= master->timer->max_instances)
278 return -EBUSY;
279 list_move_tail(&slave->open_list, &master->slave_list_head);
280 master->timer->num_instances++;
281 snd_timer_ref_get(master->timer);
282 guard(write_lock_irq)(&timeri_lock);
283 guard(spinlock)(&master->timer->lock);
284 slave->master = master;
285 slave->timer = master->timer;
286 if (slave->flags & SNDRV_TIMER_IFLG_RUNNING)
287 list_add_tail(&slave->active_list, &master->slave_active_head);
288 return 1;
289}
290
291static bool snd_timer_has_slave_key(const struct snd_timer_instance *timeri)
292{
293 return !(timeri->flags & SNDRV_TIMER_IFLG_SLAVE) &&
294 timeri->slave_class > SNDRV_TIMER_SCLASS_NONE;
295}
296
297/*
298 * look for a master instance matching with the slave id of the given slave.
299 * when found, relink the open_link of the slave.
300 *
301 * call this with register_mutex down.
302 */
303static int snd_timer_check_slave(struct snd_timer_instance *slave)
304{
305 struct snd_timer_instance *master;
306 int err = 0;
307
308 list_for_each_entry(master, &snd_timer_master_list, master_list) {
309 err = check_matching_master_slave(master, slave);
310 if (err != 0) /* match found or error */
311 goto out;
312 }
313out:
314 return err < 0 ? err : 0;
315}
316
317/*
318 * look for slave instances matching with the slave id of the given master.
319 * when found, relink the open_link of slaves.
320 *
321 * call this with register_mutex down.
322 */
323static int snd_timer_check_master(struct snd_timer_instance *master)
324{
325 struct snd_timer_instance *slave, *tmp;
326 int err = 0;
327
328 /* check all pending slaves */
329 list_for_each_entry_safe(slave, tmp, &snd_timer_slave_list, open_list) {
330 err = check_matching_master_slave(master, slave);
331 if (err < 0)
332 break;
333 }
334 return err < 0 ? err : 0;
335}
336
337static void snd_timer_close_locked(struct snd_timer_instance *timeri,
338 struct device **card_devp_to_put);
339
340/*
341 * open a timer instance
342 * when opening a master, the slave id must be here given.
343 */
344int snd_timer_open(struct snd_timer_instance *timeri,
345 struct snd_timer_id *tid,
346 unsigned int slave_id)
347{
348 struct snd_timer *timer;
349 struct device *card_dev_to_put = NULL;
350 int err;
351
352 mutex_lock(&register_mutex);
353 if (tid->dev_class == SNDRV_TIMER_CLASS_SLAVE) {
354 /* open a slave instance */
355 if (tid->dev_sclass <= SNDRV_TIMER_SCLASS_NONE ||
356 tid->dev_sclass > SNDRV_TIMER_SCLASS_OSS_SEQUENCER) {
357 pr_debug("ALSA: timer: invalid slave class %i\n",
358 tid->dev_sclass);
359 err = -EINVAL;
360 goto unlock;
361 }
362 if (num_slaves >= MAX_SLAVE_INSTANCES) {
363 err = -EBUSY;
364 goto unlock;
365 }
366 timeri->slave_class = tid->dev_sclass;
367 timeri->slave_id = tid->device;
368 timeri->flags |= SNDRV_TIMER_IFLG_SLAVE;
369 list_add_tail(&timeri->open_list, &snd_timer_slave_list);
370 num_slaves++;
371 err = snd_timer_check_slave(timeri);
372 goto list_added;
373 }
374
375 /* open a master instance */
376 timer = snd_timer_find(tid);
377#ifdef CONFIG_MODULES
378 if (!timer) {
379 mutex_unlock(&register_mutex);
380 snd_timer_request(tid);
381 mutex_lock(&register_mutex);
382 timer = snd_timer_find(tid);
383 }
384#endif
385 if (!timer) {
386 err = -ENODEV;
387 goto unlock;
388 }
389 if (!list_empty(&timer->open_list_head)) {
390 struct snd_timer_instance *t =
391 list_entry(timer->open_list_head.next,
392 struct snd_timer_instance, open_list);
393 if (t->flags & SNDRV_TIMER_IFLG_EXCLUSIVE) {
394 err = -EBUSY;
395 goto unlock;
396 }
397 }
398 if (timer->num_instances >= timer->max_instances) {
399 err = -EBUSY;
400 goto unlock;
401 }
402 if (!try_module_get(timer->module)) {
403 err = -EBUSY;
404 goto unlock;
405 }
406 /* take a card refcount for safe disconnection */
407 if (timer->card) {
408 get_device(&timer->card->card_dev);
409 card_dev_to_put = &timer->card->card_dev;
410 }
411
412 if (list_empty(&timer->open_list_head) && timer->hw.open) {
413 err = timer->hw.open(timer);
414 if (err) {
415 module_put(timer->module);
416 goto unlock;
417 }
418 }
419
420 timeri->timer = timer;
421 timeri->slave_class = tid->dev_sclass;
422 timeri->slave_id = slave_id;
423
424 list_add_tail(&timeri->open_list, &timer->open_list_head);
425 if (snd_timer_has_slave_key(timeri))
426 list_add_tail(&timeri->master_list, &snd_timer_master_list);
427 timer->num_instances++;
428 snd_timer_ref_get(timer);
429 err = snd_timer_check_master(timeri);
430list_added:
431 if (err < 0)
432 snd_timer_close_locked(timeri, &card_dev_to_put);
433
434 unlock:
435 mutex_unlock(&register_mutex);
436 /* put_device() is called after unlock for avoiding deadlock */
437 if (err < 0 && card_dev_to_put)
438 put_device(card_dev_to_put);
439 return err;
440}
441EXPORT_SYMBOL(snd_timer_open);
442
443/* remove slave links, called from snd_timer_close_locked() below */
444static void remove_slave_links(struct snd_timer_instance *timeri,
445 struct snd_timer *timer)
446{
447 struct snd_timer_instance *slave, *tmp;
448
449 guard(write_lock_irq)(&timeri_lock);
450 guard(spinlock)(&timer->lock);
451 timeri->timer = NULL;
452 list_for_each_entry_safe(slave, tmp, &timeri->slave_list_head, open_list) {
453 list_move_tail(&slave->open_list, &snd_timer_slave_list);
454 timer->num_instances--;
455 snd_timer_ref_put(timer);
456 slave->master = NULL;
457 slave->timer = NULL;
458 list_del_init(&slave->ack_list);
459 list_del_init(&slave->active_list);
460 }
461 /* the close is done; a reopen must not see the mark */
462 timeri->flags &= ~SNDRV_TIMER_IFLG_DEAD;
463}
464
465/*
466 * close a timer instance
467 * call this with register_mutex down.
468 */
469static void snd_timer_close_locked(struct snd_timer_instance *timeri,
470 struct device **card_devp_to_put)
471{
472 struct snd_timer *timer = timeri->timer;
473
474 if (timer) {
475 guard(spinlock_irq)(&timer->lock);
476 if (timeri->flags & SNDRV_TIMER_IFLG_DEAD)
477 return; /* already closed */
478 timeri->flags |= SNDRV_TIMER_IFLG_DEAD;
479 }
480
481 if (!list_empty(&timeri->open_list)) {
482 list_del_init(&timeri->open_list);
483 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
484 num_slaves--;
485 }
486
487 if (!list_empty(&timeri->master_list))
488 list_del_init(&timeri->master_list);
489
490 /* force to stop the timer */
491 snd_timer_stop(timeri);
492
493 if (timer) {
494 struct snd_timer_instance *slave;
495 bool busy;
496
497 timer->num_instances--;
498 /* unqueue then drain the slaves' callbacks before remove_slave_links() severs them */
499 spin_lock_irq(&timer->lock);
500 list_for_each_entry(slave, &timeri->slave_list_head, open_list)
501 list_del_init(&slave->ack_list);
502 for (;;) {
503 busy = timeri->flags & SNDRV_TIMER_IFLG_CALLBACK;
504 list_for_each_entry(slave, &timeri->slave_list_head, open_list)
505 busy |= slave->flags & SNDRV_TIMER_IFLG_CALLBACK;
506 if (!busy)
507 break;
508 spin_unlock_irq(&timer->lock);
509 udelay(10);
510 spin_lock_irq(&timer->lock);
511 }
512 spin_unlock_irq(&timer->lock);
513
514 remove_slave_links(timeri, timer);
515
516 /* slave doesn't need to release timer resources below */
517 if (!(timeri->flags & SNDRV_TIMER_IFLG_SLAVE)) {
518 if (list_empty(&timer->open_list_head) && timer->hw.close)
519 timer->hw.close(timer);
520 /* release a card refcount for safe disconnection */
521 if (timer->card)
522 *card_devp_to_put = &timer->card->card_dev;
523 module_put(timer->module);
524 }
525
526 snd_timer_ref_put(timer);
527 }
528}
529
530/*
531 * close a timer instance
532 */
533void snd_timer_close(struct snd_timer_instance *timeri)
534{
535 struct device *card_dev_to_put = NULL;
536
537 if (snd_BUG_ON(!timeri))
538 return;
539
540 scoped_guard(mutex, &register_mutex)
541 snd_timer_close_locked(timeri, &card_dev_to_put);
542 /* put_device() is called after unlock for avoiding deadlock */
543 if (card_dev_to_put)
544 put_device(card_dev_to_put);
545}
546EXPORT_SYMBOL(snd_timer_close);
547
548static unsigned long snd_timer_hw_resolution(struct snd_timer *timer)
549{
550 if (timer->hw.c_resolution)
551 return timer->hw.c_resolution(timer);
552 else
553 return timer->hw.resolution;
554}
555
556unsigned long snd_timer_resolution(struct snd_timer_instance *timeri)
557{
558 unsigned long ret = 0;
559
560 if (timeri == NULL)
561 return 0;
562
563 struct snd_timer *timer __free(snd_timeri_timer)
564 = snd_timeri_timer_get(timeri);
565 if (timer) {
566 guard(spinlock_irqsave)(&timer->lock);
567 ret = snd_timer_hw_resolution(timer);
568 }
569 return ret;
570}
571EXPORT_SYMBOL(snd_timer_resolution);
572
573static void snd_timer_notify1(struct snd_timer_instance *ti, int event)
574{
575 struct snd_timer *timer = ti->timer;
576 unsigned long resolution = 0;
577 struct snd_timer_instance *ts;
578 struct timespec64 tstamp;
579
580 if (timer_tstamp_monotonic)
581 ktime_get_ts64(&tstamp);
582 else
583 ktime_get_real_ts64(&tstamp);
584 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_START ||
585 event > SNDRV_TIMER_EVENT_PAUSE))
586 return;
587 if (timer &&
588 (event == SNDRV_TIMER_EVENT_START ||
589 event == SNDRV_TIMER_EVENT_CONTINUE))
590 resolution = snd_timer_hw_resolution(timer);
591 if (ti->ccallback)
592 ti->ccallback(ti, event, &tstamp, resolution);
593 if (ti->flags & SNDRV_TIMER_IFLG_SLAVE)
594 return;
595 if (timer == NULL)
596 return;
597 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
598 return;
599 event += 10; /* convert to SNDRV_TIMER_EVENT_MXXX */
600 list_for_each_entry(ts, &ti->slave_active_head, active_list)
601 if (ts->ccallback)
602 ts->ccallback(ts, event, &tstamp, resolution);
603}
604
605/* start/continue a master timer */
606static int snd_timer_start1(struct snd_timer_instance *timeri,
607 bool start, unsigned long ticks)
608{
609 struct snd_timer *timer;
610 int result;
611
612 timer = timeri->timer;
613 if (!timer)
614 return -EINVAL;
615
616 guard(spinlock)(&timer->lock);
617 if (timeri->flags & SNDRV_TIMER_IFLG_DEAD)
618 return -EINVAL;
619 if (timer->card && timer->card->shutdown)
620 return -ENODEV;
621 if (timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
622 SNDRV_TIMER_IFLG_START))
623 return -EBUSY;
624
625 /* check the actual time for the start tick;
626 * bail out as error if it's way too low (< 100us)
627 */
628 if (start && !(timer->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
629 if ((u64)snd_timer_hw_resolution(timer) * ticks < 100000)
630 return -EINVAL;
631 }
632
633 if (start)
634 timeri->ticks = timeri->cticks = ticks;
635 else if (!timeri->cticks)
636 timeri->cticks = 1;
637 timeri->pticks = 0;
638
639 list_move_tail(&timeri->active_list, &timer->active_list_head);
640 if (timer->running) {
641 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
642 goto __start_now;
643 timer->flags |= SNDRV_TIMER_FLG_RESCHED;
644 timeri->flags |= SNDRV_TIMER_IFLG_START;
645 result = 1; /* delayed start */
646 } else {
647 if (start)
648 timer->sticks = ticks;
649 timer->hw.start(timer);
650 __start_now:
651 timer->running++;
652 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
653 result = 0;
654 }
655 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
656 SNDRV_TIMER_EVENT_CONTINUE);
657 return result;
658}
659
660/* start/continue a slave timer */
661static int snd_timer_start_slave(struct snd_timer_instance *timeri,
662 bool start)
663{
664 if (timeri->flags & SNDRV_TIMER_IFLG_DEAD)
665 return -EINVAL;
666 if (timeri->flags & SNDRV_TIMER_IFLG_RUNNING)
667 return -EBUSY;
668 timeri->flags |= SNDRV_TIMER_IFLG_RUNNING;
669 if (timeri->master && timeri->timer) {
670 guard(spinlock)(&timeri->timer->lock);
671 list_add_tail(&timeri->active_list,
672 &timeri->master->slave_active_head);
673 snd_timer_notify1(timeri, start ? SNDRV_TIMER_EVENT_START :
674 SNDRV_TIMER_EVENT_CONTINUE);
675 }
676 return 1; /* delayed start */
677}
678
679/* stop/pause a master timer */
680static int snd_timer_stop1(struct snd_timer_instance *timeri, bool stop)
681{
682 struct snd_timer *timer;
683
684 timer = timeri->timer;
685 if (!timer)
686 return -EINVAL;
687 guard(spinlock)(&timer->lock);
688 list_del_init(&timeri->ack_list);
689 list_del_init(&timeri->active_list);
690 if (!(timeri->flags & (SNDRV_TIMER_IFLG_RUNNING |
691 SNDRV_TIMER_IFLG_START)))
692 return -EBUSY;
693 if (timer->card && timer->card->shutdown)
694 return 0;
695 if (stop) {
696 timeri->cticks = timeri->ticks;
697 timeri->pticks = 0;
698 }
699 if ((timeri->flags & SNDRV_TIMER_IFLG_RUNNING) &&
700 !(--timer->running)) {
701 timer->hw.stop(timer);
702 if (timer->flags & SNDRV_TIMER_FLG_RESCHED) {
703 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
704 snd_timer_reschedule(timer, 0);
705 if (timer->flags & SNDRV_TIMER_FLG_CHANGE) {
706 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
707 timer->hw.start(timer);
708 }
709 }
710 }
711 timeri->flags &= ~(SNDRV_TIMER_IFLG_RUNNING | SNDRV_TIMER_IFLG_START);
712 if (stop)
713 timeri->flags &= ~SNDRV_TIMER_IFLG_PAUSED;
714 else
715 timeri->flags |= SNDRV_TIMER_IFLG_PAUSED;
716 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
717 SNDRV_TIMER_EVENT_PAUSE);
718 return 0;
719}
720
721/* stop/pause a slave timer */
722static int snd_timer_stop_slave(struct snd_timer_instance *timeri, bool stop)
723{
724 bool running;
725
726 running = timeri->flags & SNDRV_TIMER_IFLG_RUNNING;
727 timeri->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
728 if (timeri->timer) {
729 guard(spinlock)(&timeri->timer->lock);
730 list_del_init(&timeri->ack_list);
731 list_del_init(&timeri->active_list);
732 if (running)
733 snd_timer_notify1(timeri, stop ? SNDRV_TIMER_EVENT_STOP :
734 SNDRV_TIMER_EVENT_PAUSE);
735 }
736 return running ? 0 : -EBUSY;
737}
738
739/*
740 * start the timer instance
741 */
742int snd_timer_start(struct snd_timer_instance *timeri, unsigned int ticks)
743{
744 if (timeri == NULL || ticks < 1)
745 return -EINVAL;
746 guard(read_lock_irqsave)(&timeri_lock);
747 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
748 return snd_timer_start_slave(timeri, true);
749 else
750 return snd_timer_start1(timeri, true, ticks);
751}
752EXPORT_SYMBOL(snd_timer_start);
753
754/*
755 * stop the timer instance.
756 *
757 * do not call this from the timer callback!
758 */
759int snd_timer_stop(struct snd_timer_instance *timeri)
760{
761 guard(read_lock_irqsave)(&timeri_lock);
762 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
763 return snd_timer_stop_slave(timeri, true);
764 else
765 return snd_timer_stop1(timeri, true);
766}
767EXPORT_SYMBOL(snd_timer_stop);
768
769/*
770 * start again.. the tick is kept.
771 */
772int snd_timer_continue(struct snd_timer_instance *timeri)
773{
774 /* timer can continue only after pause */
775 if (!(timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
776 return -EINVAL;
777
778 guard(read_lock_irqsave)(&timeri_lock);
779 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
780 return snd_timer_start_slave(timeri, false);
781 else
782 return snd_timer_start1(timeri, false, 0);
783}
784EXPORT_SYMBOL(snd_timer_continue);
785
786/*
787 * pause.. remember the ticks left
788 */
789int snd_timer_pause(struct snd_timer_instance * timeri)
790{
791 guard(read_lock_irqsave)(&timeri_lock);
792 if (timeri->flags & SNDRV_TIMER_IFLG_SLAVE)
793 return snd_timer_stop_slave(timeri, false);
794 else
795 return snd_timer_stop1(timeri, false);
796}
797EXPORT_SYMBOL(snd_timer_pause);
798
799/*
800 * reschedule the timer
801 *
802 * start pending instances and check the scheduling ticks.
803 * when the scheduling ticks is changed set CHANGE flag to reprogram the timer.
804 */
805static void snd_timer_reschedule(struct snd_timer * timer, unsigned long ticks_left)
806{
807 struct snd_timer_instance *ti;
808 unsigned long ticks = ~0UL;
809
810 list_for_each_entry(ti, &timer->active_list_head, active_list) {
811 if (ti->flags & SNDRV_TIMER_IFLG_START) {
812 ti->flags &= ~SNDRV_TIMER_IFLG_START;
813 ti->flags |= SNDRV_TIMER_IFLG_RUNNING;
814 timer->running++;
815 }
816 if (ti->flags & SNDRV_TIMER_IFLG_RUNNING) {
817 if (ticks > ti->cticks)
818 ticks = ti->cticks;
819 }
820 }
821 if (ticks == ~0UL) {
822 timer->flags &= ~SNDRV_TIMER_FLG_RESCHED;
823 return;
824 }
825 if (ticks > timer->hw.ticks)
826 ticks = timer->hw.ticks;
827 if (ticks_left != ticks)
828 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
829 timer->sticks = ticks;
830}
831
832/* call callbacks in timer ack list */
833static void snd_timer_process_callbacks(struct snd_timer *timer,
834 struct list_head *head)
835{
836 struct snd_timer_instance *ti;
837 unsigned long resolution, ticks;
838
839 while (!list_empty(head)) {
840 ti = list_first_entry(head, struct snd_timer_instance,
841 ack_list);
842
843 /* remove from ack_list and make empty */
844 list_del_init(&ti->ack_list);
845
846 if (!(ti->flags & SNDRV_TIMER_IFLG_DEAD)) {
847 ticks = ti->pticks;
848 ti->pticks = 0;
849 resolution = ti->resolution;
850 ti->flags |= SNDRV_TIMER_IFLG_CALLBACK;
851 spin_unlock(&timer->lock);
852 if (ti->callback)
853 ti->callback(ti, resolution, ticks);
854 spin_lock(&timer->lock);
855 ti->flags &= ~SNDRV_TIMER_IFLG_CALLBACK;
856 }
857 }
858}
859
860/* clear pending instances from ack list */
861static void snd_timer_clear_callbacks(struct snd_timer *timer,
862 struct list_head *head)
863{
864 guard(spinlock_irqsave)(&timer->lock);
865 while (!list_empty(head))
866 list_del_init(head->next);
867}
868
869/*
870 * timer work
871 *
872 */
873static void snd_timer_work(struct work_struct *work)
874{
875 struct snd_timer *timer = container_of(work, struct snd_timer, task_work);
876
877 if (timer->card && timer->card->shutdown) {
878 snd_timer_clear_callbacks(timer, &timer->sack_list_head);
879 return;
880 }
881
882 guard(spinlock_irqsave)(&timer->lock);
883 snd_timer_process_callbacks(timer, &timer->sack_list_head);
884}
885
886/*
887 * timer interrupt
888 *
889 * ticks_left is usually equal to timer->sticks.
890 *
891 */
892void snd_timer_interrupt(struct snd_timer * timer, unsigned long ticks_left)
893{
894 struct snd_timer_instance *ti, *ts, *tmp;
895 unsigned long resolution;
896 struct list_head *ack_list_head;
897
898 if (timer == NULL)
899 return;
900
901 if (timer->card && timer->card->shutdown) {
902 snd_timer_clear_callbacks(timer, &timer->ack_list_head);
903 return;
904 }
905
906 guard(spinlock_irqsave)(&timer->lock);
907
908 /* remember the current resolution */
909 resolution = snd_timer_hw_resolution(timer);
910
911 /* loop for all active instances
912 * Here we cannot use list_for_each_entry because the active_list of a
913 * processed instance is relinked to done_list_head before the callback
914 * is called.
915 */
916 list_for_each_entry_safe(ti, tmp, &timer->active_list_head,
917 active_list) {
918 if (ti->flags & SNDRV_TIMER_IFLG_DEAD)
919 continue;
920 if (!(ti->flags & SNDRV_TIMER_IFLG_RUNNING))
921 continue;
922 ti->pticks += ticks_left;
923 ti->resolution = resolution;
924 if (ti->cticks < ticks_left)
925 ti->cticks = 0;
926 else
927 ti->cticks -= ticks_left;
928 if (ti->cticks) /* not expired */
929 continue;
930 if (ti->flags & SNDRV_TIMER_IFLG_AUTO) {
931 ti->cticks = ti->ticks;
932 } else {
933 ti->flags &= ~SNDRV_TIMER_IFLG_RUNNING;
934 --timer->running;
935 list_del_init(&ti->active_list);
936 }
937 if ((timer->hw.flags & SNDRV_TIMER_HW_WORK) ||
938 (ti->flags & SNDRV_TIMER_IFLG_FAST))
939 ack_list_head = &timer->ack_list_head;
940 else
941 ack_list_head = &timer->sack_list_head;
942 /* don't requeue an instance whose callback is still running */
943 if (list_empty(&ti->ack_list) &&
944 !(ti->flags & SNDRV_TIMER_IFLG_CALLBACK))
945 list_add_tail(&ti->ack_list, ack_list_head);
946 list_for_each_entry(ts, &ti->slave_active_head, active_list) {
947 ts->pticks = ti->pticks;
948 ts->resolution = resolution;
949 if (list_empty(&ts->ack_list) &&
950 !(ts->flags & SNDRV_TIMER_IFLG_CALLBACK))
951 list_add_tail(&ts->ack_list, ack_list_head);
952 }
953 }
954 if (timer->flags & SNDRV_TIMER_FLG_RESCHED)
955 snd_timer_reschedule(timer, timer->sticks);
956 if (timer->running) {
957 if (timer->hw.flags & SNDRV_TIMER_HW_STOP) {
958 timer->hw.stop(timer);
959 timer->flags |= SNDRV_TIMER_FLG_CHANGE;
960 }
961 if (!(timer->hw.flags & SNDRV_TIMER_HW_AUTO) ||
962 (timer->flags & SNDRV_TIMER_FLG_CHANGE)) {
963 /* restart timer */
964 timer->flags &= ~SNDRV_TIMER_FLG_CHANGE;
965 timer->hw.start(timer);
966 }
967 } else {
968 timer->hw.stop(timer);
969 }
970
971 /* now process all fast callbacks */
972 snd_timer_process_callbacks(timer, &timer->ack_list_head);
973
974 /* do we have any slow callbacks? */
975 if (!list_empty(&timer->sack_list_head))
976 queue_work(system_highpri_wq, &timer->task_work);
977}
978EXPORT_SYMBOL(snd_timer_interrupt);
979
980/*
981
982 */
983
984int snd_timer_new(struct snd_card *card, char *id, struct snd_timer_id *tid,
985 struct snd_timer **rtimer)
986{
987 struct snd_timer *timer;
988 int err;
989 static const struct snd_device_ops ops = {
990 .dev_free = snd_timer_dev_free,
991 .dev_register = snd_timer_dev_register,
992 .dev_disconnect = snd_timer_dev_disconnect,
993 };
994
995 if (snd_BUG_ON(!tid))
996 return -EINVAL;
997 if (tid->dev_class == SNDRV_TIMER_CLASS_CARD ||
998 tid->dev_class == SNDRV_TIMER_CLASS_PCM) {
999 if (WARN_ON(!card))
1000 return -EINVAL;
1001 }
1002 if (rtimer)
1003 *rtimer = NULL;
1004 timer = kzalloc_obj(*timer);
1005 if (!timer)
1006 return -ENOMEM;
1007 timer->tmr_class = tid->dev_class;
1008 timer->card = card;
1009 timer->tmr_device = tid->device;
1010 timer->tmr_subdevice = tid->subdevice;
1011 if (id)
1012 strscpy(timer->id, id, sizeof(timer->id));
1013 timer->sticks = 1;
1014 INIT_LIST_HEAD(&timer->device_list);
1015 INIT_LIST_HEAD(&timer->open_list_head);
1016 INIT_LIST_HEAD(&timer->active_list_head);
1017 INIT_LIST_HEAD(&timer->ack_list_head);
1018 INIT_LIST_HEAD(&timer->sack_list_head);
1019 spin_lock_init(&timer->lock);
1020 INIT_WORK(&timer->task_work, snd_timer_work);
1021 timer->max_instances = 1000; /* default limit per timer */
1022 kref_init(&timer->kref);
1023 if (card != NULL) {
1024 timer->module = card->module;
1025 err = snd_device_new(card, SNDRV_DEV_TIMER, timer, &ops);
1026 if (err < 0) {
1027 snd_timer_free(timer);
1028 return err;
1029 }
1030 }
1031 if (rtimer)
1032 *rtimer = timer;
1033 return 0;
1034}
1035EXPORT_SYMBOL(snd_timer_new);
1036
1037static void snd_timer_kref_release(struct kref *kref)
1038{
1039 struct snd_timer *timer = container_of(kref, struct snd_timer, kref);
1040
1041 if (timer->private_free)
1042 timer->private_free(timer);
1043 kfree(timer);
1044}
1045
1046static int snd_timer_free(struct snd_timer *timer)
1047{
1048 struct snd_timer_instance *ti, *n;
1049
1050 if (!timer)
1051 return 0;
1052
1053 scoped_guard(mutex, &register_mutex) {
1054 if (!list_empty(&timer->open_list_head)) {
1055 list_for_each_entry_safe(ti, n, &timer->open_list_head, open_list) {
1056 struct device *card_dev_to_put = NULL;
1057
1058 snd_timer_close_locked(ti, &card_dev_to_put);
1059 put_device(card_dev_to_put);
1060 }
1061 }
1062 list_del(&timer->device_list);
1063 }
1064
1065 disable_work_sync(&timer->task_work);
1066
1067 snd_timer_ref_put(timer);
1068 return 0;
1069}
1070
1071static int snd_timer_dev_free(struct snd_device *device)
1072{
1073 struct snd_timer *timer = device->device_data;
1074 return snd_timer_free(timer);
1075}
1076
1077static int snd_timer_dev_register(struct snd_device *dev)
1078{
1079 struct snd_timer *timer = dev->device_data;
1080 struct snd_timer *timer1;
1081 struct list_head *insert_before = &snd_timer_list;
1082
1083 if (snd_BUG_ON(!timer || !timer->hw.start || !timer->hw.stop))
1084 return -ENXIO;
1085 if (!(timer->hw.flags & SNDRV_TIMER_HW_SLAVE) &&
1086 !timer->hw.resolution && timer->hw.c_resolution == NULL)
1087 return -EINVAL;
1088
1089 guard(mutex)(&register_mutex);
1090 list_for_each_entry(timer1, &snd_timer_list, device_list) {
1091 if (timer1->tmr_class > timer->tmr_class) {
1092 insert_before = &timer1->device_list;
1093 break;
1094 }
1095 if (timer1->tmr_class < timer->tmr_class)
1096 continue;
1097 if (timer1->card && timer->card) {
1098 if (timer1->card->number > timer->card->number) {
1099 insert_before = &timer1->device_list;
1100 break;
1101 }
1102 if (timer1->card->number < timer->card->number)
1103 continue;
1104 }
1105 if (timer1->tmr_device > timer->tmr_device) {
1106 insert_before = &timer1->device_list;
1107 break;
1108 }
1109 if (timer1->tmr_device < timer->tmr_device)
1110 continue;
1111 if (timer1->tmr_subdevice > timer->tmr_subdevice) {
1112 insert_before = &timer1->device_list;
1113 break;
1114 }
1115 if (timer1->tmr_subdevice < timer->tmr_subdevice)
1116 continue;
1117 /* conflicts.. */
1118 return -EBUSY;
1119 }
1120 list_add_tail(&timer->device_list, insert_before);
1121 return 0;
1122}
1123
1124static int snd_timer_dev_disconnect(struct snd_device *device)
1125{
1126 struct snd_timer *timer = device->device_data;
1127 struct snd_timer_instance *ti;
1128
1129 guard(mutex)(&register_mutex);
1130 list_del_init(&timer->device_list);
1131 /* wake up pending sleepers */
1132 list_for_each_entry(ti, &timer->open_list_head, open_list) {
1133 if (ti->disconnect)
1134 ti->disconnect(ti);
1135 }
1136 return 0;
1137}
1138
1139void snd_timer_notify(struct snd_timer *timer, int event, struct timespec64 *tstamp)
1140{
1141 unsigned long resolution = 0;
1142 struct snd_timer_instance *ti, *ts;
1143
1144 if (timer->card && timer->card->shutdown)
1145 return;
1146 if (! (timer->hw.flags & SNDRV_TIMER_HW_SLAVE))
1147 return;
1148 if (snd_BUG_ON(event < SNDRV_TIMER_EVENT_MSTART ||
1149 event > SNDRV_TIMER_EVENT_MRESUME))
1150 return;
1151 guard(spinlock_irqsave)(&timer->lock);
1152 if (event == SNDRV_TIMER_EVENT_MSTART ||
1153 event == SNDRV_TIMER_EVENT_MCONTINUE ||
1154 event == SNDRV_TIMER_EVENT_MRESUME)
1155 resolution = snd_timer_hw_resolution(timer);
1156 list_for_each_entry(ti, &timer->active_list_head, active_list) {
1157 if (ti->ccallback)
1158 ti->ccallback(ti, event, tstamp, resolution);
1159 list_for_each_entry(ts, &ti->slave_active_head, active_list)
1160 if (ts->ccallback)
1161 ts->ccallback(ts, event, tstamp, resolution);
1162 }
1163}
1164EXPORT_SYMBOL(snd_timer_notify);
1165
1166/*
1167 * exported functions for global timers
1168 */
1169int snd_timer_global_new(char *id, int device, struct snd_timer **rtimer)
1170{
1171 struct snd_timer_id tid;
1172
1173 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
1174 tid.dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1175 tid.card = -1;
1176 tid.device = device;
1177 tid.subdevice = 0;
1178 return snd_timer_new(NULL, id, &tid, rtimer);
1179}
1180EXPORT_SYMBOL(snd_timer_global_new);
1181
1182int snd_timer_global_free(struct snd_timer *timer)
1183{
1184 return snd_timer_free(timer);
1185}
1186EXPORT_SYMBOL(snd_timer_global_free);
1187
1188int snd_timer_global_register(struct snd_timer *timer)
1189{
1190 struct snd_device dev;
1191
1192 memset(&dev, 0, sizeof(dev));
1193 dev.device_data = timer;
1194 return snd_timer_dev_register(&dev);
1195}
1196EXPORT_SYMBOL(snd_timer_global_register);
1197
1198/*
1199 * System timer
1200 */
1201
1202struct snd_timer_system_private {
1203 struct timer_list tlist;
1204 struct snd_timer *snd_timer;
1205 unsigned long last_expires;
1206 unsigned long last_jiffies;
1207 unsigned long correction;
1208};
1209
1210static void snd_timer_s_function(struct timer_list *t)
1211{
1212 struct snd_timer_system_private *priv = timer_container_of(priv, t,
1213 tlist);
1214 struct snd_timer *timer = priv->snd_timer;
1215 unsigned long jiff = jiffies;
1216 if (time_after(jiff, priv->last_expires))
1217 priv->correction += (long)jiff - (long)priv->last_expires;
1218 snd_timer_interrupt(timer, (long)jiff - (long)priv->last_jiffies);
1219}
1220
1221static int snd_timer_s_start(struct snd_timer * timer)
1222{
1223 struct snd_timer_system_private *priv;
1224 unsigned long njiff;
1225
1226 priv = (struct snd_timer_system_private *) timer->private_data;
1227 njiff = (priv->last_jiffies = jiffies);
1228 if (priv->correction > timer->sticks - 1) {
1229 priv->correction -= timer->sticks - 1;
1230 njiff++;
1231 } else {
1232 njiff += timer->sticks - priv->correction;
1233 priv->correction = 0;
1234 }
1235 priv->last_expires = njiff;
1236 mod_timer(&priv->tlist, njiff);
1237 return 0;
1238}
1239
1240static int snd_timer_s_stop(struct snd_timer * timer)
1241{
1242 struct snd_timer_system_private *priv;
1243 unsigned long jiff;
1244
1245 priv = (struct snd_timer_system_private *) timer->private_data;
1246 timer_delete(&priv->tlist);
1247 jiff = jiffies;
1248 if (time_before(jiff, priv->last_expires))
1249 timer->sticks = priv->last_expires - jiff;
1250 else
1251 timer->sticks = 1;
1252 priv->correction = 0;
1253 return 0;
1254}
1255
1256static int snd_timer_s_close(struct snd_timer *timer)
1257{
1258 struct snd_timer_system_private *priv;
1259
1260 priv = (struct snd_timer_system_private *)timer->private_data;
1261 timer_delete_sync(&priv->tlist);
1262 return 0;
1263}
1264
1265static const struct snd_timer_hardware snd_timer_system =
1266{
1267 .flags = SNDRV_TIMER_HW_FIRST | SNDRV_TIMER_HW_WORK,
1268 .resolution = NSEC_PER_SEC / HZ,
1269 .ticks = 10000000L,
1270 .close = snd_timer_s_close,
1271 .start = snd_timer_s_start,
1272 .stop = snd_timer_s_stop
1273};
1274
1275static void snd_timer_free_system(struct snd_timer *timer)
1276{
1277 kfree(timer->private_data);
1278}
1279
1280static int snd_timer_register_system(void)
1281{
1282 struct snd_timer *timer;
1283 struct snd_timer_system_private *priv;
1284 int err;
1285
1286 err = snd_timer_global_new("system", SNDRV_TIMER_GLOBAL_SYSTEM, &timer);
1287 if (err < 0)
1288 return err;
1289 strscpy(timer->name, "system timer");
1290 timer->hw = snd_timer_system;
1291 priv = kzalloc_obj(*priv);
1292 if (priv == NULL) {
1293 snd_timer_free(timer);
1294 return -ENOMEM;
1295 }
1296 priv->snd_timer = timer;
1297 timer_setup(&priv->tlist, snd_timer_s_function, 0);
1298 timer->private_data = priv;
1299 timer->private_free = snd_timer_free_system;
1300 return snd_timer_global_register(timer);
1301}
1302
1303#ifdef CONFIG_SND_PROC_FS
1304/*
1305 * Info interface
1306 */
1307
1308static void snd_timer_proc_read(struct snd_info_entry *entry,
1309 struct snd_info_buffer *buffer)
1310{
1311 struct snd_timer *timer;
1312 struct snd_timer_instance *ti;
1313 unsigned long resolution;
1314
1315 guard(mutex)(&register_mutex);
1316 list_for_each_entry(timer, &snd_timer_list, device_list) {
1317 if (timer->card && timer->card->shutdown)
1318 continue;
1319 switch (timer->tmr_class) {
1320 case SNDRV_TIMER_CLASS_GLOBAL:
1321 snd_iprintf(buffer, "G%i: ", timer->tmr_device);
1322 break;
1323 case SNDRV_TIMER_CLASS_CARD:
1324 snd_iprintf(buffer, "C%i-%i: ",
1325 timer->card->number, timer->tmr_device);
1326 break;
1327 case SNDRV_TIMER_CLASS_PCM:
1328 snd_iprintf(buffer, "P%i-%i-%i: ", timer->card->number,
1329 timer->tmr_device, timer->tmr_subdevice);
1330 break;
1331 default:
1332 snd_iprintf(buffer, "?%i-%i-%i-%i: ", timer->tmr_class,
1333 timer->card ? timer->card->number : -1,
1334 timer->tmr_device, timer->tmr_subdevice);
1335 }
1336 snd_iprintf(buffer, "%s :", timer->name);
1337 scoped_guard(spinlock_irq, &timer->lock)
1338 resolution = snd_timer_hw_resolution(timer);
1339 if (resolution)
1340 snd_iprintf(buffer, " %lu.%03luus (%lu ticks)",
1341 resolution / 1000,
1342 resolution % 1000,
1343 timer->hw.ticks);
1344 if (timer->hw.flags & SNDRV_TIMER_HW_SLAVE)
1345 snd_iprintf(buffer, " SLAVE");
1346 snd_iprintf(buffer, "\n");
1347 list_for_each_entry(ti, &timer->open_list_head, open_list)
1348 snd_iprintf(buffer, " Client %s : %s\n",
1349 ti->owner ? ti->owner : "unknown",
1350 (ti->flags & (SNDRV_TIMER_IFLG_START |
1351 SNDRV_TIMER_IFLG_RUNNING))
1352 ? "running" : "stopped");
1353 }
1354}
1355
1356static struct snd_info_entry *snd_timer_proc_entry;
1357
1358static void __init snd_timer_proc_init(void)
1359{
1360 struct snd_info_entry *entry;
1361
1362 entry = snd_info_create_module_entry(THIS_MODULE, "timers", NULL);
1363 if (entry != NULL) {
1364 entry->c.text.read = snd_timer_proc_read;
1365 if (snd_info_register(entry) < 0) {
1366 snd_info_free_entry(entry);
1367 entry = NULL;
1368 }
1369 }
1370 snd_timer_proc_entry = entry;
1371}
1372
1373static void __exit snd_timer_proc_done(void)
1374{
1375 snd_info_free_entry(snd_timer_proc_entry);
1376}
1377#else /* !CONFIG_SND_PROC_FS */
1378#define snd_timer_proc_init()
1379#define snd_timer_proc_done()
1380#endif
1381
1382/*
1383 * USER SPACE interface
1384 */
1385
1386static void snd_timer_user_interrupt(struct snd_timer_instance *timeri,
1387 unsigned long resolution,
1388 unsigned long ticks)
1389{
1390 struct snd_timer_user *tu = timeri->callback_data;
1391 struct snd_timer_read *r;
1392 int prev;
1393
1394 guard(spinlock)(&tu->qlock);
1395 if (tu->qused > 0) {
1396 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1397 r = &tu->queue[prev];
1398 if (r->resolution == resolution) {
1399 r->ticks += ticks;
1400 goto __wake;
1401 }
1402 }
1403 if (tu->qused >= tu->queue_size) {
1404 tu->overrun++;
1405 } else {
1406 r = &tu->queue[tu->qtail++];
1407 tu->qtail %= tu->queue_size;
1408 r->resolution = resolution;
1409 r->ticks = ticks;
1410 tu->qused++;
1411 }
1412 __wake:
1413 snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1414 wake_up(&tu->qchange_sleep);
1415}
1416
1417static void snd_timer_user_append_to_tqueue(struct snd_timer_user *tu,
1418 struct snd_timer_tread64 *tread)
1419{
1420 if (tu->qused >= tu->queue_size) {
1421 tu->overrun++;
1422 } else {
1423 memcpy(&tu->tqueue[tu->qtail++], tread, sizeof(*tread));
1424 tu->qtail %= tu->queue_size;
1425 tu->qused++;
1426 }
1427}
1428
1429static void snd_timer_user_ccallback(struct snd_timer_instance *timeri,
1430 int event,
1431 struct timespec64 *tstamp,
1432 unsigned long resolution)
1433{
1434 struct snd_timer_user *tu = timeri->callback_data;
1435 struct snd_timer_tread64 r1;
1436
1437 if (event >= SNDRV_TIMER_EVENT_START &&
1438 event <= SNDRV_TIMER_EVENT_PAUSE)
1439 tu->tstamp = *tstamp;
1440 if ((tu->filter & (1 << event)) == 0 || !tu->tread)
1441 return;
1442 memset(&r1, 0, sizeof(r1));
1443 r1.event = event;
1444 r1.tstamp_sec = tstamp->tv_sec;
1445 r1.tstamp_nsec = tstamp->tv_nsec;
1446 r1.val = resolution;
1447 scoped_guard(spinlock_irqsave, &tu->qlock)
1448 snd_timer_user_append_to_tqueue(tu, &r1);
1449 snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1450 wake_up(&tu->qchange_sleep);
1451}
1452
1453static void snd_timer_user_disconnect(struct snd_timer_instance *timeri)
1454{
1455 struct snd_timer_user *tu = timeri->callback_data;
1456
1457 tu->disconnected = true;
1458 wake_up(&tu->qchange_sleep);
1459}
1460
1461static void snd_timer_user_tinterrupt(struct snd_timer_instance *timeri,
1462 unsigned long resolution,
1463 unsigned long ticks)
1464{
1465 struct snd_timer_user *tu = timeri->callback_data;
1466 struct snd_timer_tread64 *r, r1;
1467 struct timespec64 tstamp;
1468 int prev, append = 0;
1469
1470 memset(&r1, 0, sizeof(r1));
1471 memset(&tstamp, 0, sizeof(tstamp));
1472 scoped_guard(spinlock, &tu->qlock) {
1473 if ((tu->filter & ((1 << SNDRV_TIMER_EVENT_RESOLUTION) |
1474 (1 << SNDRV_TIMER_EVENT_TICK))) == 0)
1475 return;
1476 if (tu->last_resolution != resolution || ticks > 0) {
1477 if (timer_tstamp_monotonic)
1478 ktime_get_ts64(&tstamp);
1479 else
1480 ktime_get_real_ts64(&tstamp);
1481 }
1482 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_RESOLUTION)) &&
1483 tu->last_resolution != resolution) {
1484 r1.event = SNDRV_TIMER_EVENT_RESOLUTION;
1485 r1.tstamp_sec = tstamp.tv_sec;
1486 r1.tstamp_nsec = tstamp.tv_nsec;
1487 r1.val = resolution;
1488 snd_timer_user_append_to_tqueue(tu, &r1);
1489 tu->last_resolution = resolution;
1490 append++;
1491 }
1492 if ((tu->filter & (1 << SNDRV_TIMER_EVENT_TICK)) == 0)
1493 break;
1494 if (ticks == 0)
1495 break;
1496 if (tu->qused > 0) {
1497 prev = tu->qtail == 0 ? tu->queue_size - 1 : tu->qtail - 1;
1498 r = &tu->tqueue[prev];
1499 if (r->event == SNDRV_TIMER_EVENT_TICK) {
1500 r->tstamp_sec = tstamp.tv_sec;
1501 r->tstamp_nsec = tstamp.tv_nsec;
1502 r->val += ticks;
1503 append++;
1504 break;
1505 }
1506 }
1507 r1.event = SNDRV_TIMER_EVENT_TICK;
1508 r1.tstamp_sec = tstamp.tv_sec;
1509 r1.tstamp_nsec = tstamp.tv_nsec;
1510 r1.val = ticks;
1511 snd_timer_user_append_to_tqueue(tu, &r1);
1512 append++;
1513 }
1514 if (append == 0)
1515 return;
1516 snd_kill_fasync(tu->fasync, SIGIO, POLL_IN);
1517 wake_up(&tu->qchange_sleep);
1518}
1519
1520static int realloc_user_queue(struct snd_timer_user *tu, int size)
1521{
1522 struct snd_timer_read *queue = NULL;
1523 struct snd_timer_tread64 *tqueue = NULL;
1524
1525 if (tu->tread) {
1526 tqueue = kzalloc_objs(*tqueue, size);
1527 if (!tqueue)
1528 return -ENOMEM;
1529 } else {
1530 queue = kzalloc_objs(*queue, size);
1531 if (!queue)
1532 return -ENOMEM;
1533 }
1534
1535 guard(spinlock_irq)(&tu->qlock);
1536 kfree(tu->queue);
1537 kfree(tu->tqueue);
1538 tu->queue_size = size;
1539 tu->queue = queue;
1540 tu->tqueue = tqueue;
1541 tu->qhead = tu->qtail = tu->qused = 0;
1542
1543 return 0;
1544}
1545
1546static int snd_timer_user_open(struct inode *inode, struct file *file)
1547{
1548 struct snd_timer_user *tu;
1549
1550 stream_open(inode, file);
1551
1552 tu = kzalloc_obj(*tu);
1553 if (tu == NULL)
1554 return -ENOMEM;
1555 spin_lock_init(&tu->qlock);
1556 init_waitqueue_head(&tu->qchange_sleep);
1557 mutex_init(&tu->ioctl_lock);
1558 tu->ticks = 1;
1559 if (realloc_user_queue(tu, 128) < 0) {
1560 kfree(tu);
1561 return -ENOMEM;
1562 }
1563 file->private_data = tu;
1564 return 0;
1565}
1566
1567static int snd_timer_user_release(struct inode *inode, struct file *file)
1568{
1569 struct snd_timer_user *tu;
1570
1571 if (file->private_data) {
1572 tu = file->private_data;
1573 file->private_data = NULL;
1574 scoped_guard(mutex, &tu->ioctl_lock) {
1575 if (tu->timeri) {
1576 snd_timer_close(tu->timeri);
1577 snd_timer_instance_free(tu->timeri);
1578 }
1579 }
1580 snd_fasync_free(tu->fasync);
1581 kfree(tu->queue);
1582 kfree(tu->tqueue);
1583 kfree(tu);
1584 }
1585 return 0;
1586}
1587
1588static void snd_timer_user_zero_id(struct snd_timer_id *id)
1589{
1590 id->dev_class = SNDRV_TIMER_CLASS_NONE;
1591 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1592 id->card = -1;
1593 id->device = -1;
1594 id->subdevice = -1;
1595}
1596
1597static void snd_timer_user_copy_id(struct snd_timer_id *id, struct snd_timer *timer)
1598{
1599 id->dev_class = timer->tmr_class;
1600 id->dev_sclass = SNDRV_TIMER_SCLASS_NONE;
1601 id->card = timer->card ? timer->card->number : -1;
1602 id->device = timer->tmr_device;
1603 id->subdevice = timer->tmr_subdevice;
1604}
1605
1606static void get_next_device(struct snd_timer_id *id)
1607{
1608 struct snd_timer *timer;
1609 struct list_head *p;
1610
1611 if (id->dev_class < 0) { /* first item */
1612 if (list_empty(&snd_timer_list))
1613 snd_timer_user_zero_id(id);
1614 else {
1615 timer = list_entry(snd_timer_list.next,
1616 struct snd_timer, device_list);
1617 snd_timer_user_copy_id(id, timer);
1618 }
1619 } else {
1620 switch (id->dev_class) {
1621 case SNDRV_TIMER_CLASS_GLOBAL:
1622 id->device = id->device < 0 ? 0 : id->device + 1;
1623 list_for_each(p, &snd_timer_list) {
1624 timer = list_entry(p, struct snd_timer, device_list);
1625 if (timer->tmr_class > SNDRV_TIMER_CLASS_GLOBAL) {
1626 snd_timer_user_copy_id(id, timer);
1627 break;
1628 }
1629 if (timer->tmr_device >= id->device) {
1630 snd_timer_user_copy_id(id, timer);
1631 break;
1632 }
1633 }
1634 if (p == &snd_timer_list)
1635 snd_timer_user_zero_id(id);
1636 break;
1637 case SNDRV_TIMER_CLASS_CARD:
1638 case SNDRV_TIMER_CLASS_PCM:
1639 if (id->card < 0) {
1640 id->card = 0;
1641 } else {
1642 if (id->device < 0) {
1643 id->device = 0;
1644 } else {
1645 if (id->subdevice < 0)
1646 id->subdevice = 0;
1647 else if (id->subdevice < INT_MAX)
1648 id->subdevice++;
1649 }
1650 }
1651 list_for_each(p, &snd_timer_list) {
1652 timer = list_entry(p, struct snd_timer, device_list);
1653 if (timer->tmr_class > id->dev_class) {
1654 snd_timer_user_copy_id(id, timer);
1655 break;
1656 }
1657 if (timer->tmr_class < id->dev_class)
1658 continue;
1659 if (timer->card->number > id->card) {
1660 snd_timer_user_copy_id(id, timer);
1661 break;
1662 }
1663 if (timer->card->number < id->card)
1664 continue;
1665 if (timer->tmr_device > id->device) {
1666 snd_timer_user_copy_id(id, timer);
1667 break;
1668 }
1669 if (timer->tmr_device < id->device)
1670 continue;
1671 if (timer->tmr_subdevice > id->subdevice) {
1672 snd_timer_user_copy_id(id, timer);
1673 break;
1674 }
1675 if (timer->tmr_subdevice < id->subdevice)
1676 continue;
1677 snd_timer_user_copy_id(id, timer);
1678 break;
1679 }
1680 if (p == &snd_timer_list)
1681 snd_timer_user_zero_id(id);
1682 break;
1683 default:
1684 snd_timer_user_zero_id(id);
1685 }
1686 }
1687}
1688
1689static int snd_timer_user_next_device(struct snd_timer_id __user *_tid)
1690{
1691 struct snd_timer_id id;
1692
1693 if (copy_from_user(&id, _tid, sizeof(id)))
1694 return -EFAULT;
1695 scoped_guard(mutex, &register_mutex)
1696 get_next_device(&id);
1697 if (copy_to_user(_tid, &id, sizeof(*_tid)))
1698 return -EFAULT;
1699 return 0;
1700}
1701
1702static int snd_timer_user_ginfo(struct file *file,
1703 struct snd_timer_ginfo __user *_ginfo)
1704{
1705 struct snd_timer_id tid;
1706 struct snd_timer *t;
1707 struct list_head *p;
1708 struct snd_timer_ginfo *ginfo __free(kfree) =
1709 memdup_user(_ginfo, sizeof(*ginfo));
1710
1711 if (IS_ERR(ginfo))
1712 return PTR_ERR(ginfo);
1713
1714 tid = ginfo->tid;
1715 memset(ginfo, 0, sizeof(*ginfo));
1716 ginfo->tid = tid;
1717 scoped_guard(mutex, &register_mutex) {
1718 t = snd_timer_find(&tid);
1719 if (!t)
1720 return -ENODEV;
1721 ginfo->card = t->card ? t->card->number : -1;
1722 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1723 ginfo->flags |= SNDRV_TIMER_FLG_SLAVE;
1724 strscpy(ginfo->id, t->id, sizeof(ginfo->id));
1725 strscpy(ginfo->name, t->name, sizeof(ginfo->name));
1726 scoped_guard(spinlock_irq, &t->lock)
1727 ginfo->resolution = snd_timer_hw_resolution(t);
1728 if (t->hw.resolution_min > 0) {
1729 ginfo->resolution_min = t->hw.resolution_min;
1730 ginfo->resolution_max = t->hw.resolution_max;
1731 }
1732 list_for_each(p, &t->open_list_head) {
1733 ginfo->clients++;
1734 }
1735 }
1736 if (copy_to_user(_ginfo, ginfo, sizeof(*ginfo)))
1737 return -EFAULT;
1738 return 0;
1739}
1740
1741static int timer_set_gparams(struct snd_timer_gparams *gparams)
1742{
1743 struct snd_timer *t;
1744
1745 guard(mutex)(&register_mutex);
1746 t = snd_timer_find(&gparams->tid);
1747 if (!t)
1748 return -ENODEV;
1749 if (!list_empty(&t->open_list_head))
1750 return -EBUSY;
1751 if (!t->hw.set_period)
1752 return -ENOSYS;
1753 return t->hw.set_period(t, gparams->period_num, gparams->period_den);
1754}
1755
1756static int snd_timer_user_gparams(struct file *file,
1757 struct snd_timer_gparams __user *_gparams)
1758{
1759 struct snd_timer_gparams gparams;
1760
1761 if (copy_from_user(&gparams, _gparams, sizeof(gparams)))
1762 return -EFAULT;
1763 return timer_set_gparams(&gparams);
1764}
1765
1766static int snd_timer_user_gstatus(struct file *file,
1767 struct snd_timer_gstatus __user *_gstatus)
1768{
1769 struct snd_timer_gstatus gstatus;
1770 struct snd_timer_id tid;
1771 struct snd_timer *t;
1772
1773 if (copy_from_user(&gstatus, _gstatus, sizeof(gstatus)))
1774 return -EFAULT;
1775 tid = gstatus.tid;
1776 memset(&gstatus, 0, sizeof(gstatus));
1777 gstatus.tid = tid;
1778 scoped_guard(mutex, &register_mutex) {
1779 t = snd_timer_find(&tid);
1780 if (t != NULL) {
1781 guard(spinlock_irq)(&t->lock);
1782 gstatus.resolution = snd_timer_hw_resolution(t);
1783 if (t->hw.precise_resolution) {
1784 t->hw.precise_resolution(t, &gstatus.resolution_num,
1785 &gstatus.resolution_den);
1786 } else {
1787 gstatus.resolution_num = gstatus.resolution;
1788 gstatus.resolution_den = 1000000000uL;
1789 }
1790 } else {
1791 return -ENODEV;
1792 }
1793 }
1794 if (copy_to_user(_gstatus, &gstatus, sizeof(gstatus)))
1795 return -EFAULT;
1796 return 0;
1797}
1798
1799static int snd_timer_user_tselect(struct file *file,
1800 struct snd_timer_select __user *_tselect)
1801{
1802 struct snd_timer_user *tu;
1803 struct snd_timer_select tselect;
1804 char str[32];
1805 int err = 0;
1806
1807 tu = file->private_data;
1808 if (tu->timeri) {
1809 snd_timer_close(tu->timeri);
1810 snd_timer_instance_free(tu->timeri);
1811 tu->timeri = NULL;
1812 }
1813 if (copy_from_user(&tselect, _tselect, sizeof(tselect))) {
1814 err = -EFAULT;
1815 goto __err;
1816 }
1817 sprintf(str, "application %i", current->pid);
1818 if (tselect.id.dev_class != SNDRV_TIMER_CLASS_SLAVE)
1819 tselect.id.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
1820 tu->timeri = snd_timer_instance_new(str);
1821 if (!tu->timeri) {
1822 err = -ENOMEM;
1823 goto __err;
1824 }
1825
1826 tu->timeri->flags |= SNDRV_TIMER_IFLG_FAST;
1827 tu->timeri->callback = tu->tread
1828 ? snd_timer_user_tinterrupt : snd_timer_user_interrupt;
1829 tu->timeri->ccallback = snd_timer_user_ccallback;
1830 tu->timeri->callback_data = (void *)tu;
1831 tu->timeri->disconnect = snd_timer_user_disconnect;
1832
1833 err = snd_timer_open(tu->timeri, &tselect.id, current->pid);
1834 if (err < 0) {
1835 snd_timer_instance_free(tu->timeri);
1836 tu->timeri = NULL;
1837 }
1838
1839 __err:
1840 return err;
1841}
1842
1843static int snd_timer_user_info(struct file *file,
1844 struct snd_timer_info __user *_info)
1845{
1846 struct snd_timer_user *tu;
1847
1848 tu = file->private_data;
1849 if (!tu->timeri)
1850 return -EBADFD;
1851
1852 struct snd_timer *t __free(snd_timeri_timer) =
1853 snd_timeri_timer_get(tu->timeri);
1854 if (!t)
1855 return -EBADFD;
1856
1857 struct snd_timer_info *info __free(kfree) =
1858 kzalloc_obj(*info);
1859 if (! info)
1860 return -ENOMEM;
1861 info->card = t->card ? t->card->number : -1;
1862 if (t->hw.flags & SNDRV_TIMER_HW_SLAVE)
1863 info->flags |= SNDRV_TIMER_FLG_SLAVE;
1864 strscpy(info->id, t->id, sizeof(info->id));
1865 strscpy(info->name, t->name, sizeof(info->name));
1866 scoped_guard(spinlock_irq, &t->lock)
1867 info->resolution = snd_timer_hw_resolution(t);
1868 if (copy_to_user(_info, info, sizeof(*_info)))
1869 return -EFAULT;
1870 return 0;
1871}
1872
1873static int snd_timer_user_params(struct file *file,
1874 struct snd_timer_params __user *_params)
1875{
1876 struct snd_timer_user *tu;
1877 struct snd_timer_params params;
1878 int err;
1879
1880 tu = file->private_data;
1881 if (!tu->timeri)
1882 return -EBADFD;
1883
1884 struct snd_timer *t __free(snd_timeri_timer) =
1885 snd_timeri_timer_get(tu->timeri);
1886 if (!t)
1887 return -EBADFD;
1888 if (copy_from_user(&params, _params, sizeof(params)))
1889 return -EFAULT;
1890 if (!(t->hw.flags & SNDRV_TIMER_HW_SLAVE)) {
1891 u64 resolution;
1892
1893 if (params.ticks < 1) {
1894 err = -EINVAL;
1895 goto _end;
1896 }
1897
1898 /* Don't allow resolution less than 1ms */
1899 resolution = snd_timer_resolution(tu->timeri);
1900 resolution *= params.ticks;
1901 if (resolution < 1000000) {
1902 err = -EINVAL;
1903 goto _end;
1904 }
1905 }
1906 if (params.queue_size > 0 &&
1907 (params.queue_size < 32 || params.queue_size > 1024)) {
1908 err = -EINVAL;
1909 goto _end;
1910 }
1911 if (params.filter & ~((1<<SNDRV_TIMER_EVENT_RESOLUTION)|
1912 (1<<SNDRV_TIMER_EVENT_TICK)|
1913 (1<<SNDRV_TIMER_EVENT_START)|
1914 (1<<SNDRV_TIMER_EVENT_STOP)|
1915 (1<<SNDRV_TIMER_EVENT_CONTINUE)|
1916 (1<<SNDRV_TIMER_EVENT_PAUSE)|
1917 (1<<SNDRV_TIMER_EVENT_SUSPEND)|
1918 (1<<SNDRV_TIMER_EVENT_RESUME)|
1919 (1<<SNDRV_TIMER_EVENT_MSTART)|
1920 (1<<SNDRV_TIMER_EVENT_MSTOP)|
1921 (1<<SNDRV_TIMER_EVENT_MCONTINUE)|
1922 (1<<SNDRV_TIMER_EVENT_MPAUSE)|
1923 (1<<SNDRV_TIMER_EVENT_MSUSPEND)|
1924 (1<<SNDRV_TIMER_EVENT_MRESUME))) {
1925 err = -EINVAL;
1926 goto _end;
1927 }
1928 snd_timer_stop(tu->timeri);
1929 scoped_guard(spinlock_irq, &t->lock) {
1930 tu->timeri->flags &= ~(SNDRV_TIMER_IFLG_AUTO|
1931 SNDRV_TIMER_IFLG_EXCLUSIVE|
1932 SNDRV_TIMER_IFLG_EARLY_EVENT);
1933 if (params.flags & SNDRV_TIMER_PSFLG_AUTO)
1934 tu->timeri->flags |= SNDRV_TIMER_IFLG_AUTO;
1935 if (params.flags & SNDRV_TIMER_PSFLG_EXCLUSIVE)
1936 tu->timeri->flags |= SNDRV_TIMER_IFLG_EXCLUSIVE;
1937 if (params.flags & SNDRV_TIMER_PSFLG_EARLY_EVENT)
1938 tu->timeri->flags |= SNDRV_TIMER_IFLG_EARLY_EVENT;
1939 }
1940 if (params.queue_size > 0 &&
1941 (unsigned int)tu->queue_size != params.queue_size) {
1942 err = realloc_user_queue(tu, params.queue_size);
1943 if (err < 0)
1944 goto _end;
1945 }
1946 scoped_guard(spinlock_irq, &tu->qlock) {
1947 tu->qhead = tu->qtail = tu->qused = 0;
1948 if (tu->timeri->flags & SNDRV_TIMER_IFLG_EARLY_EVENT) {
1949 if (tu->tread) {
1950 struct snd_timer_tread64 tread;
1951
1952 memset(&tread, 0, sizeof(tread));
1953 tread.event = SNDRV_TIMER_EVENT_EARLY;
1954 tread.tstamp_sec = 0;
1955 tread.tstamp_nsec = 0;
1956 tread.val = 0;
1957 snd_timer_user_append_to_tqueue(tu, &tread);
1958 } else {
1959 struct snd_timer_read *r = &tu->queue[0];
1960
1961 r->resolution = 0;
1962 r->ticks = 0;
1963 tu->qused++;
1964 tu->qtail++;
1965 }
1966 }
1967 tu->filter = params.filter;
1968 tu->ticks = params.ticks;
1969 }
1970 err = 0;
1971 _end:
1972 if (copy_to_user(_params, &params, sizeof(params)))
1973 return -EFAULT;
1974 return err;
1975}
1976
1977static int snd_timer_user_status32(struct file *file,
1978 struct snd_timer_status32 __user *_status)
1979 {
1980 struct snd_timer_user *tu;
1981 struct snd_timer_status32 status;
1982
1983 tu = file->private_data;
1984 if (!tu->timeri)
1985 return -EBADFD;
1986 memset(&status, 0, sizeof(status));
1987 status.tstamp_sec = tu->tstamp.tv_sec;
1988 status.tstamp_nsec = tu->tstamp.tv_nsec;
1989 status.resolution = snd_timer_resolution(tu->timeri);
1990 status.lost = tu->timeri->lost;
1991 status.overrun = tu->overrun;
1992 scoped_guard(spinlock_irq, &tu->qlock)
1993 status.queue = tu->qused;
1994 if (copy_to_user(_status, &status, sizeof(status)))
1995 return -EFAULT;
1996 return 0;
1997}
1998
1999static int snd_timer_user_status64(struct file *file,
2000 struct snd_timer_status64 __user *_status)
2001{
2002 struct snd_timer_user *tu;
2003 struct snd_timer_status64 status;
2004
2005 tu = file->private_data;
2006 if (!tu->timeri)
2007 return -EBADFD;
2008 memset(&status, 0, sizeof(status));
2009 status.tstamp_sec = tu->tstamp.tv_sec;
2010 status.tstamp_nsec = tu->tstamp.tv_nsec;
2011 status.resolution = snd_timer_resolution(tu->timeri);
2012 status.lost = tu->timeri->lost;
2013 status.overrun = tu->overrun;
2014 scoped_guard(spinlock_irq, &tu->qlock)
2015 status.queue = tu->qused;
2016 if (copy_to_user(_status, &status, sizeof(status)))
2017 return -EFAULT;
2018 return 0;
2019}
2020
2021static int snd_timer_user_start(struct file *file)
2022{
2023 int err;
2024 struct snd_timer_user *tu;
2025
2026 tu = file->private_data;
2027 if (!tu->timeri)
2028 return -EBADFD;
2029 snd_timer_stop(tu->timeri);
2030 tu->timeri->lost = 0;
2031 tu->last_resolution = 0;
2032 err = snd_timer_start(tu->timeri, tu->ticks);
2033 if (err < 0)
2034 return err;
2035 return 0;
2036}
2037
2038static int snd_timer_user_stop(struct file *file)
2039{
2040 int err;
2041 struct snd_timer_user *tu;
2042
2043 tu = file->private_data;
2044 if (!tu->timeri)
2045 return -EBADFD;
2046 err = snd_timer_stop(tu->timeri);
2047 if (err < 0)
2048 return err;
2049 return 0;
2050}
2051
2052static int snd_timer_user_continue(struct file *file)
2053{
2054 int err;
2055 struct snd_timer_user *tu;
2056
2057 tu = file->private_data;
2058 if (!tu->timeri)
2059 return -EBADFD;
2060 /* start timer instead of continue if it's not used before */
2061 if (!(tu->timeri->flags & SNDRV_TIMER_IFLG_PAUSED))
2062 return snd_timer_user_start(file);
2063 tu->timeri->lost = 0;
2064 err = snd_timer_continue(tu->timeri);
2065 if (err < 0)
2066 return err;
2067 return 0;
2068}
2069
2070static int snd_timer_user_pause(struct file *file)
2071{
2072 int err;
2073 struct snd_timer_user *tu;
2074
2075 tu = file->private_data;
2076 if (!tu->timeri)
2077 return -EBADFD;
2078 err = snd_timer_pause(tu->timeri);
2079 if (err < 0)
2080 return err;
2081 return 0;
2082}
2083
2084static int snd_timer_user_tread(void __user *argp, struct snd_timer_user *tu,
2085 unsigned int cmd, bool compat)
2086{
2087 int __user *p = argp;
2088 int xarg, old_tread;
2089
2090 if (tu->timeri) /* too late */
2091 return -EBUSY;
2092 if (get_user(xarg, p))
2093 return -EFAULT;
2094
2095 old_tread = tu->tread;
2096
2097 if (!xarg)
2098 tu->tread = TREAD_FORMAT_NONE;
2099 else if (cmd == SNDRV_TIMER_IOCTL_TREAD64 ||
2100 (IS_ENABLED(CONFIG_64BIT) && !compat))
2101 tu->tread = TREAD_FORMAT_TIME64;
2102 else
2103 tu->tread = TREAD_FORMAT_TIME32;
2104
2105 if (tu->tread != old_tread &&
2106 realloc_user_queue(tu, tu->queue_size) < 0) {
2107 tu->tread = old_tread;
2108 return -ENOMEM;
2109 }
2110
2111 return 0;
2112}
2113
2114enum {
2115 SNDRV_TIMER_IOCTL_START_OLD = _IO('T', 0x20),
2116 SNDRV_TIMER_IOCTL_STOP_OLD = _IO('T', 0x21),
2117 SNDRV_TIMER_IOCTL_CONTINUE_OLD = _IO('T', 0x22),
2118 SNDRV_TIMER_IOCTL_PAUSE_OLD = _IO('T', 0x23),
2119};
2120
2121#ifdef CONFIG_SND_UTIMER
2122/*
2123 * Since userspace-driven timers are passed to userspace, we need to have an identifier
2124 * which will allow us to use them (basically, the subdevice number of udriven timer).
2125 */
2126static DEFINE_IDA(snd_utimer_ids);
2127
2128static void snd_utimer_put_id(struct snd_utimer *utimer)
2129{
2130 int timer_id = utimer->id;
2131
2132 snd_BUG_ON(timer_id < 0 || timer_id >= SNDRV_UTIMERS_MAX_COUNT);
2133 ida_free(&snd_utimer_ids, timer_id);
2134}
2135
2136static int snd_utimer_take_id(void)
2137{
2138 return ida_alloc_max(&snd_utimer_ids, SNDRV_UTIMERS_MAX_COUNT - 1, GFP_KERNEL);
2139}
2140
2141static void snd_utimer_free(struct snd_utimer *utimer)
2142{
2143 snd_timer_free(utimer->timer);
2144 snd_utimer_put_id(utimer);
2145 kfree(utimer->name);
2146 kfree(utimer);
2147}
2148
2149static int snd_utimer_release(struct inode *inode, struct file *file)
2150{
2151 struct snd_utimer *utimer = (struct snd_utimer *)file->private_data;
2152
2153 snd_utimer_free(utimer);
2154 return 0;
2155}
2156
2157static int snd_utimer_trigger(struct file *file)
2158{
2159 struct snd_utimer *utimer = (struct snd_utimer *)file->private_data;
2160
2161 snd_timer_interrupt(utimer->timer, utimer->timer->sticks);
2162 return 0;
2163}
2164
2165static long snd_utimer_ioctl(struct file *file, unsigned int ioctl, unsigned long arg)
2166{
2167 switch (ioctl) {
2168 case SNDRV_TIMER_IOCTL_TRIGGER:
2169 return snd_utimer_trigger(file);
2170 }
2171
2172 return -ENOTTY;
2173}
2174
2175static const struct file_operations snd_utimer_fops = {
2176 .llseek = noop_llseek,
2177 .release = snd_utimer_release,
2178 .unlocked_ioctl = snd_utimer_ioctl,
2179};
2180
2181static int snd_utimer_start(struct snd_timer *t)
2182{
2183 return 0;
2184}
2185
2186static int snd_utimer_stop(struct snd_timer *t)
2187{
2188 return 0;
2189}
2190
2191static int snd_utimer_open(struct snd_timer *t)
2192{
2193 return 0;
2194}
2195
2196static int snd_utimer_close(struct snd_timer *t)
2197{
2198 return 0;
2199}
2200
2201static const struct snd_timer_hardware timer_hw = {
2202 .flags = SNDRV_TIMER_HW_AUTO | SNDRV_TIMER_HW_WORK,
2203 .open = snd_utimer_open,
2204 .close = snd_utimer_close,
2205 .start = snd_utimer_start,
2206 .stop = snd_utimer_stop,
2207};
2208
2209static int snd_utimer_create(struct snd_timer_uinfo *utimer_info,
2210 struct snd_utimer **r_utimer)
2211{
2212 struct snd_utimer *utimer;
2213 struct snd_timer *timer;
2214 struct snd_timer_id tid;
2215 int utimer_id;
2216 int err = 0;
2217
2218 if (!utimer_info || utimer_info->resolution == 0)
2219 return -EINVAL;
2220
2221 utimer = kzalloc_obj(*utimer);
2222 if (!utimer)
2223 return -ENOMEM;
2224
2225 /* We hold the ioctl lock here so we won't get a race condition when allocating id */
2226 utimer_id = snd_utimer_take_id();
2227 if (utimer_id < 0) {
2228 err = utimer_id;
2229 goto err_take_id;
2230 }
2231
2232 utimer->id = utimer_id;
2233
2234 utimer->name = kasprintf(GFP_KERNEL, "snd-utimer%d", utimer_id);
2235 if (!utimer->name) {
2236 err = -ENOMEM;
2237 goto err_get_name;
2238 }
2239
2240 tid.dev_sclass = SNDRV_TIMER_SCLASS_APPLICATION;
2241 tid.dev_class = SNDRV_TIMER_CLASS_GLOBAL;
2242 tid.card = -1;
2243 tid.device = SNDRV_TIMER_GLOBAL_UDRIVEN;
2244 tid.subdevice = utimer_id;
2245
2246 err = snd_timer_new(NULL, utimer->name, &tid, &timer);
2247 if (err < 0) {
2248 pr_err("Can't create userspace-driven timer\n");
2249 goto err_timer_new;
2250 }
2251
2252 timer->module = THIS_MODULE;
2253 timer->hw = timer_hw;
2254 timer->hw.resolution = utimer_info->resolution;
2255 timer->hw.ticks = 1;
2256 timer->max_instances = MAX_SLAVE_INSTANCES;
2257
2258 utimer->timer = timer;
2259
2260 err = snd_timer_global_register(timer);
2261 if (err < 0) {
2262 pr_err("Can't register a userspace-driven timer\n");
2263 goto err_timer_reg;
2264 }
2265
2266 *r_utimer = utimer;
2267 return 0;
2268
2269err_timer_reg:
2270 snd_timer_free(timer);
2271err_timer_new:
2272 kfree(utimer->name);
2273err_get_name:
2274 snd_utimer_put_id(utimer);
2275err_take_id:
2276 kfree(utimer);
2277
2278 return err;
2279}
2280
2281static int snd_utimer_ioctl_create(struct file *file,
2282 struct snd_timer_uinfo __user *_utimer_info)
2283{
2284 struct snd_utimer *utimer;
2285 int err, timer_fd;
2286 struct snd_timer_uinfo *utimer_info __free(kfree) =
2287 memdup_user(_utimer_info, sizeof(*utimer_info));
2288
2289 if (IS_ERR(utimer_info))
2290 return PTR_ERR(utimer_info);
2291
2292 err = snd_utimer_create(utimer_info, &utimer);
2293 if (err < 0)
2294 return err;
2295
2296 utimer_info->id = utimer->id;
2297
2298 timer_fd = anon_inode_getfd(utimer->name, &snd_utimer_fops, utimer, O_RDWR | O_CLOEXEC);
2299 if (timer_fd < 0) {
2300 snd_utimer_free(utimer);
2301 return timer_fd;
2302 }
2303
2304 utimer_info->fd = timer_fd;
2305
2306 err = copy_to_user(_utimer_info, utimer_info, sizeof(*utimer_info));
2307 if (err) {
2308 /*
2309 * "Leak" the fd, as there is nothing we can do about it.
2310 * It might have been closed already since anon_inode_getfd
2311 * makes it available for userspace.
2312 *
2313 * We have to rely on the process exit path to do any
2314 * necessary cleanup (e.g. releasing the file).
2315 */
2316 return -EFAULT;
2317 }
2318
2319 return 0;
2320}
2321
2322#else
2323
2324static int snd_utimer_ioctl_create(struct file *file,
2325 struct snd_timer_uinfo __user *_utimer_info)
2326{
2327 return -ENOTTY;
2328}
2329
2330#endif
2331
2332static long __snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2333 unsigned long arg, bool compat)
2334{
2335 struct snd_timer_user *tu;
2336 void __user *argp = (void __user *)arg;
2337 int __user *p = argp;
2338
2339 tu = file->private_data;
2340 switch (cmd) {
2341 case SNDRV_TIMER_IOCTL_PVERSION:
2342 return put_user(SNDRV_TIMER_VERSION, p) ? -EFAULT : 0;
2343 case SNDRV_TIMER_IOCTL_NEXT_DEVICE:
2344 return snd_timer_user_next_device(argp);
2345 case SNDRV_TIMER_IOCTL_TREAD_OLD:
2346 case SNDRV_TIMER_IOCTL_TREAD64:
2347 return snd_timer_user_tread(argp, tu, cmd, compat);
2348 case SNDRV_TIMER_IOCTL_GINFO:
2349 return snd_timer_user_ginfo(file, argp);
2350 case SNDRV_TIMER_IOCTL_GPARAMS:
2351 return snd_timer_user_gparams(file, argp);
2352 case SNDRV_TIMER_IOCTL_GSTATUS:
2353 return snd_timer_user_gstatus(file, argp);
2354 case SNDRV_TIMER_IOCTL_SELECT:
2355 return snd_timer_user_tselect(file, argp);
2356 case SNDRV_TIMER_IOCTL_INFO:
2357 return snd_timer_user_info(file, argp);
2358 case SNDRV_TIMER_IOCTL_PARAMS:
2359 return snd_timer_user_params(file, argp);
2360 case SNDRV_TIMER_IOCTL_STATUS32:
2361 return snd_timer_user_status32(file, argp);
2362 case SNDRV_TIMER_IOCTL_STATUS64:
2363 return snd_timer_user_status64(file, argp);
2364 case SNDRV_TIMER_IOCTL_START:
2365 case SNDRV_TIMER_IOCTL_START_OLD:
2366 return snd_timer_user_start(file);
2367 case SNDRV_TIMER_IOCTL_STOP:
2368 case SNDRV_TIMER_IOCTL_STOP_OLD:
2369 return snd_timer_user_stop(file);
2370 case SNDRV_TIMER_IOCTL_CONTINUE:
2371 case SNDRV_TIMER_IOCTL_CONTINUE_OLD:
2372 return snd_timer_user_continue(file);
2373 case SNDRV_TIMER_IOCTL_PAUSE:
2374 case SNDRV_TIMER_IOCTL_PAUSE_OLD:
2375 return snd_timer_user_pause(file);
2376 case SNDRV_TIMER_IOCTL_CREATE:
2377 return snd_utimer_ioctl_create(file, argp);
2378 }
2379 return -ENOTTY;
2380}
2381
2382static long snd_timer_user_ioctl(struct file *file, unsigned int cmd,
2383 unsigned long arg)
2384{
2385 struct snd_timer_user *tu = file->private_data;
2386
2387 guard(mutex)(&tu->ioctl_lock);
2388 return __snd_timer_user_ioctl(file, cmd, arg, false);
2389}
2390
2391static int snd_timer_user_fasync(int fd, struct file * file, int on)
2392{
2393 struct snd_timer_user *tu;
2394
2395 tu = file->private_data;
2396 return snd_fasync_helper(fd, file, on, &tu->fasync);
2397}
2398
2399static ssize_t snd_timer_user_read(struct file *file, char __user *buffer,
2400 size_t count, loff_t *offset)
2401{
2402 struct snd_timer_tread64 *tread;
2403 struct snd_timer_tread32 tread32;
2404 struct snd_timer_user *tu;
2405 long result = 0, unit;
2406 int qhead;
2407 int err = 0;
2408
2409 tu = file->private_data;
2410 switch (tu->tread) {
2411 case TREAD_FORMAT_TIME64:
2412 unit = sizeof(struct snd_timer_tread64);
2413 break;
2414 case TREAD_FORMAT_TIME32:
2415 unit = sizeof(struct snd_timer_tread32);
2416 break;
2417 case TREAD_FORMAT_NONE:
2418 unit = sizeof(struct snd_timer_read);
2419 break;
2420 default:
2421 WARN_ONCE(1, "Corrupt snd_timer_user\n");
2422 return -ENOTSUPP;
2423 }
2424
2425 mutex_lock(&tu->ioctl_lock);
2426 spin_lock_irq(&tu->qlock);
2427 while ((long)count - result >= unit) {
2428 while (!tu->qused) {
2429 wait_queue_entry_t wait;
2430
2431 if ((file->f_flags & O_NONBLOCK) != 0 || result > 0) {
2432 err = -EAGAIN;
2433 goto _error;
2434 }
2435
2436 set_current_state(TASK_INTERRUPTIBLE);
2437 init_waitqueue_entry(&wait, current);
2438 add_wait_queue(&tu->qchange_sleep, &wait);
2439
2440 spin_unlock_irq(&tu->qlock);
2441 mutex_unlock(&tu->ioctl_lock);
2442 schedule();
2443 mutex_lock(&tu->ioctl_lock);
2444 spin_lock_irq(&tu->qlock);
2445
2446 remove_wait_queue(&tu->qchange_sleep, &wait);
2447
2448 if (tu->disconnected) {
2449 err = -ENODEV;
2450 goto _error;
2451 }
2452 if (signal_pending(current)) {
2453 err = -ERESTARTSYS;
2454 goto _error;
2455 }
2456 }
2457
2458 qhead = tu->qhead++;
2459 tu->qhead %= tu->queue_size;
2460 tu->qused--;
2461 spin_unlock_irq(&tu->qlock);
2462
2463 tread = &tu->tqueue[qhead];
2464
2465 switch (tu->tread) {
2466 case TREAD_FORMAT_TIME64:
2467 if (copy_to_user(buffer, tread,
2468 sizeof(struct snd_timer_tread64)))
2469 err = -EFAULT;
2470 break;
2471 case TREAD_FORMAT_TIME32:
2472 memset(&tread32, 0, sizeof(tread32));
2473 tread32 = (struct snd_timer_tread32) {
2474 .event = tread->event,
2475 .tstamp_sec = tread->tstamp_sec,
2476 .tstamp_nsec = tread->tstamp_nsec,
2477 .val = tread->val,
2478 };
2479
2480 if (copy_to_user(buffer, &tread32, sizeof(tread32)))
2481 err = -EFAULT;
2482 break;
2483 case TREAD_FORMAT_NONE:
2484 if (copy_to_user(buffer, &tu->queue[qhead],
2485 sizeof(struct snd_timer_read)))
2486 err = -EFAULT;
2487 break;
2488 default:
2489 err = -ENOTSUPP;
2490 break;
2491 }
2492
2493 spin_lock_irq(&tu->qlock);
2494 if (err < 0)
2495 goto _error;
2496 result += unit;
2497 buffer += unit;
2498 }
2499 _error:
2500 spin_unlock_irq(&tu->qlock);
2501 mutex_unlock(&tu->ioctl_lock);
2502 return result > 0 ? result : err;
2503}
2504
2505static __poll_t snd_timer_user_poll(struct file *file, poll_table * wait)
2506{
2507 __poll_t mask;
2508 struct snd_timer_user *tu;
2509
2510 tu = file->private_data;
2511
2512 poll_wait(file, &tu->qchange_sleep, wait);
2513
2514 mask = 0;
2515 guard(spinlock_irq)(&tu->qlock);
2516 if (tu->qused)
2517 mask |= EPOLLIN | EPOLLRDNORM;
2518 if (tu->disconnected)
2519 mask |= EPOLLERR;
2520
2521 return mask;
2522}
2523
2524#ifdef CONFIG_COMPAT
2525#include "timer_compat.c"
2526#else
2527#define snd_timer_user_ioctl_compat NULL
2528#endif
2529
2530static const struct file_operations snd_timer_f_ops = {
2531 .owner = THIS_MODULE,
2532 .read = snd_timer_user_read,
2533 .open = snd_timer_user_open,
2534 .release = snd_timer_user_release,
2535 .poll = snd_timer_user_poll,
2536 .unlocked_ioctl = snd_timer_user_ioctl,
2537 .compat_ioctl = snd_timer_user_ioctl_compat,
2538 .fasync = snd_timer_user_fasync,
2539};
2540
2541/* unregister the system timer */
2542static void snd_timer_free_all(void)
2543{
2544 struct snd_timer *timer, *n;
2545
2546 list_for_each_entry_safe(timer, n, &snd_timer_list, device_list)
2547 snd_timer_free(timer);
2548}
2549
2550static struct device *timer_dev;
2551
2552/*
2553 * ENTRY functions
2554 */
2555
2556static int __init alsa_timer_init(void)
2557{
2558 int err;
2559
2560 err = snd_device_alloc(&timer_dev, NULL);
2561 if (err < 0)
2562 return err;
2563 dev_set_name(timer_dev, "timer");
2564
2565#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2566 snd_oss_info_register(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1,
2567 "system timer");
2568#endif
2569
2570 err = snd_timer_register_system();
2571 if (err < 0) {
2572 pr_err("ALSA: unable to register system timer (%i)\n", err);
2573 goto put_timer;
2574 }
2575
2576 err = snd_register_device(SNDRV_DEVICE_TYPE_TIMER, NULL, 0,
2577 &snd_timer_f_ops, NULL, timer_dev);
2578 if (err < 0) {
2579 pr_err("ALSA: unable to register timer device (%i)\n", err);
2580 snd_timer_free_all();
2581 goto put_timer;
2582 }
2583
2584 snd_timer_proc_init();
2585 return 0;
2586
2587put_timer:
2588 put_device(timer_dev);
2589 return err;
2590}
2591
2592static void __exit alsa_timer_exit(void)
2593{
2594 snd_unregister_device(timer_dev);
2595 snd_timer_free_all();
2596 put_device(timer_dev);
2597 snd_timer_proc_done();
2598#ifdef SNDRV_OSS_INFO_DEV_TIMERS
2599 snd_oss_info_unregister(SNDRV_OSS_INFO_DEV_TIMERS, SNDRV_CARDS - 1);
2600#endif
2601}
2602
2603module_init(alsa_timer_init)
2604module_exit(alsa_timer_exit)